Are you a first time visiter to Tokyo? If you are using Narita Airpot, this video might help you find what's the best way for ya. 

So I bet a lot of traveler's choice of hotel location would be Shinjuku. If you are one of them use N'EX or Limousine Bus if you don't mind paying 3,000 yen (roughly 27USD). If you're on a budget and don't mind carrying your suitcase to Tokyo Station, use Keisei Bus, also known as Tokyo Shuttle. 

Paolo and I usually use N'EX because it's the fastest way and never be late. On the other hand, any bus could be late when there's traffic on the highway. 

Just to note, if you're taking express trains or regular trains to get to the roading spot of the buses, to go to Narita Airport, depending on the station you might have to go around for the elevators or escalators. So remember to leave early. (Shibuya and Shinjuku are such a big and complicated station. I had to do research to find the best way to get to the N'EX platform of Shibuya Station!)

Hope the video helps! Let me know if you need more information or need any help with transportations by commenting on the comment section.